Detecting motion in digital video can be used in context with a variety of image processing applications. For example, inter-frame motion detection can be used in connection with addressing blur that is perceived by the human eye when viewing the frames on a hold-type display, such as a liquid crystal display. However, detection of inter-frame motion is difficult to perform quickly and accurately. For example, detecting global inter-frame motion can be computationally expensive, cause processing delays, and require large amounts of memory. To address these problems video frames are sometimes compressed prior to detecting inter-frame motion. A color video frame or image may be compressed by using a bit plane of the image, which is a monochrome image. However, the selected bit plane used for inter-frame motion detection can vary depending on luminance levels in the image and the type of scene depicted in the image.